Denied unemployment, how do I appeal? (Milwaukee)

I got a denial letter last week saying I left my job voluntarily, but I was let go as a security officer. I have read a lot of threads here and could not find my exact situation. The letter lists a deadline and a hearing process, but it is hard to follow. Should I ask someone for free legal help?

Stay calm and stick to facts. Mine lasted about thirty minutes and felt more like a conversation than a trial.